460 EXPEEIMENT STATION RECORD. 



for each station the dates on which the mean temperature normally reaches 

 75° and 69°. Attention is called to the fact that the usefulness of the set of 

 maps showing when seed ticks will have starved to death is not limited to the 

 starvation method of eradication, since if the dipping method is used it is just 

 as important to know when the fields will be cleared, for to dip too long causes 

 unnecessary expense, while to stop dipping too soon Is to throw away a whole 

 season's work. 



The cattle tick, H. A. Reid {Jour. New Zeal. Dept. Agr., 3 (1911), No. 4, 

 pp. Sl-'i, 315, figs. 2). — The author records the occurrence of Ixodes ricimis in 

 New Zealand for the first time. 



New species of ticks (Haemaphysalis, Amblyomina), L. E. Robinson {Para- 

 sitology, Jf {1911), No. //, pp. -'/7'S-//i'//. figs. //). — Two species and 1 variety are 

 described as new, namely, //. silacea, taken at East London, South Africa, from 

 cattle allowed to run on a " starvation camp " from which stock had been ex- 

 cluded for 2 years; A. flebrigi, collected at San Bernardino, Paraguay (host 

 not specified) ; and A. variegatum nocens, which has "become notorious among 

 Ehodesian stock owners as the 'pysema tick.' It is attributed to be the causa- 

 tive agent in the transmission of pyolymphangitis in equines ; its bites are so 

 severe as to cause violent inflammation and sloughing of the mammse in cows. 

 It also attacks the heads of native children, causing sloughing of portions of 

 the scalp." 



Some researches on the life cycle of spirochetes, H. B. Fantham {Ann. 

 Trop. Med. and Par., 5 {1911), No. 3, pp. 479-1,96, figs. 6).— "The spirochetes 

 considered in this paper are Spirochwta dutioni, 8. recurrentis, and S. marchotixi 

 {'=gallinarxim) among blood-inhabiting forms, also S. balManii In Ostrea edulis 

 and Tapes aures, S. anodontw in Anodonta eygnea and 8. soJenis in Soleuensis. 

 Both living and stained material have been used. True longitudinal division, 

 as well as transverse division has been observed in these spirochetes. There is 

 a periodicity in the division of the blood-inhabiting spirochetes, transverse divi- 

 sion occurring when the parasites are numerous in the blood, longitudinal divi- 

 sion occurring at the beginning and end of infection. . . . 



"Certain 8. duttoni, when ingested by Omithodorus moubata, and certain 

 8. galliiiarum ingested by Argas persicus pass through the Intestinal wall of 

 their ho.sts, and then form minute coccoid bodies, spores, or ' granules ' by 

 multiple transverse fission. Such granules, as well as spirochetes, may be found 

 in the haemocoelic fluid of the ticks, in the Malpighian tubules, and in tlhe 

 gonads. Some of the spirochetes and spores reach the ovaries and ova of the 

 infected parent tick. The spores concentrate in the Malpighian tubules of the 

 developing embryo, which may be born infected. Many nymphs of O. moubata 

 born of infected parents are themselves capable of infecting. In the case of 

 nymphs of Argas persicus, although various observers have recorded negative 

 results, more experiments are necessary before it can be asserted that nymphs 

 born of infected pax'ents are themselves not infective. The main source of 

 infection from both adult and young ticks is the white excrement passed from 

 the Malpighian tubules. Elongation of the coccoid bodies, spores, or ' granules ' 

 to form short rods, and growth of these rods to form longer (or vibrio) forms 

 has been observed in the tick. In this way young spirochetes are developed." 



A bibliography of 26 titles is appended. 



On the life cycle of Spirochseta gallinarum, E. Hindle {Parasitology, 4 

 {1911), No. Ji, pp. J,63-Jfl7, figs. 6').— "The life cycle of 8. gallinarum may be 

 briefly summarized as follows: Commencing with the ordinary parasite in the 

 blood of the fowl, the spirochete grows until it reaches a certain length 

 (16ai-19m) and then divides by the peculiar mode of transverse division de- 

 scribed above. This process is repeated and is probably the only method of 



